When Must a Knife be Cleaned and Sanitized? (How To Clean it)

There are three possible scenarios when it comes to knife cleaning and sanitation The first and most common one is using a knife for a specific purpose. The second scenario is using a knife for more than one thing, The third scenario is an uncommon one is when multiple people use a knife.

The first and most common one is using a knife for a specific purpose. If you are the only person using that knife and you’ve used it to cut meat alone, then it’s safe to say you should only clean it after you use it.

The second scenario is using a knife for more than one thing. You are still the only person using that knife, but this time you want to cut two different types of food like red meat and fish. You need to wash your knife when you finish with red meat – before you use it to cut fish. If you are using it for more things (e.g., meat, fish, poultry, and more) you need to wash it in between each one. It’s best to use different cutting boards for each food as well.

The third scenario, an uncommon one, is when multiple people use a knife. Because you don’t know when the knife was last sanitized (or if they did a good job) you need to clean it before you use it. The first and second scenario rules still apply: Clean it in between different types of food and after you finish using it.

Why is it important to clean and sanitize knives?

Saying that dirty knives are dangerous seems rather extreme. But the truth is, it is. If you don’t properly clean and sanitize your knives you can kill someone. Cross-contamination (what happens when you don’t properly clean your knives between each use) is a dangerous and potentially lethal problem.

When Must a Knife be Cleaned and Sanitized?

If you don’t clean your knives properly, you can easily transfer viruses and bacteria from one food to another. And even if most viruses and bacteria die past a certain temperature (e.g., cooking temperatures) you can potentially harm someone when you cut something that does not need to go over the fire.

Cross-contamination can also be dangerous even if no viruses or bacteria are around. You might unintentionally expose someone to a food allergen. In the best-case scenario, they have a bad day in the hospital – in the worst-case scenario, they die.

How often should you clean your knives?

As you know, it depends. You will usually clean your knives after each use or between different food types. If you haven’t used a knife for a long time, it’s best to clean it before as well. If it’s a new knife, make sure you thoroughly clean it before you use it for the first time.

How do you properly clean a knife?

There are two things you need to worry about when it comes to knife sanitation: safety and procedure.

You should clean your knives by hand. Make sure you are always paying attention to the task at hand to avoid cutting yourself. Always grab the knife by the handle to avoid any problems. Speaking of handles, some of them have a shape that makes it easier to collect food debris unintentionally, make sure you check those spots and leave no food buildup there.

You need to use the right type of detergent for the job. You can damage your knife beyond repair with the wrong detergent. Make sure you are not using an aggressive detergent to clean your knives to avoid staining or dulling the metal.

Once you’ve taken the necessary precautions, cleaning a knife is rather straightforward: rinse the knife, apply detergent, and thoroughly clean the blade. Check if the handle is clean and without food buildup. After you finish, make sure the knife is completely dry before you store it.

Can I use my dishwasher to clean a knife?

You can, but you shouldn’t. Even though several knives are “dishwasher-proof”, you are bound to ruin a knife by washing it in the dishwasher several times in a row. The heat will most likely damage the handle too. And the blade will hit several things inside the dishwasher, possibly ruining both. Excess water can also increase the risk of developing rust. Food from other kitchen elements (pans, pots, plates, etc.) can permanently stain your knife as well.

If you consider all possible problems, you can understand why a dishwasher is not the best strategy when it comes to cleaning a knife. It might seem more convenient, but only in a short-term period.

What happens if I don’t clean my knives right or as often as I should?

As you know, not cleaning your knives is potentially dangerous for humans because of cross-contamination. And it’s also not good for knives themselves. A dirty knife can potentially develop rust and become dull. You can also permanently stain your blade if you don’t wash it right away.

How can you tell you’ve done a good job cleaning your knife?

If you have done a good job, your knife will look as good as new! Or as close as it can get, depending on how old it is. You should have no food debris on the blade nor buildup on the handle. It should smell like nothing but metal (and perhaps detergent.)

Remember you are not finished once you have cleaned your knife – you need to dry it as well to finish the job!

Are certain knives past the point of no return when it comes to cleaning them?

It’s highly unlikely that you face a knife in such a poor state you cannot bring it back to life. But sometimes it will be cheaper to buy a new knife than to restore a damaged one. Always consider how much it’s going to cost before you decide to restore a damaged knife.

Is there anything else I should take care of?

Yes! Make sure your cutting boards are as clean as your knives are – as long as you’re cleaning them, that is. You should also routinely check your knife block: turn it upside down, take a closer look for an inspection, and clean it even if you find nothing. Make sure it’s completely dry before you place your knives back in.

This is the one thing I felt were super useful when I clean my knife.

Joseph Joseph BladeBrush Knife and Cutlery Cleaner Brush Bristle Scrub Kitchen Washing Non-Slip, One Size, Gray
  • Clean sharp blades safely
  • Unique, wrap-around design cleans both sides at...
  • Opposed bristles for effective cleaning
  • Textured handgrip
  • Wash by hand

Last update on 2024-05-04 / Affiliate links / Images from Amazon Product Advertising API


I’m Ahmed, the guy behind Knifepulse.com. I’ve owned several types of knives and sharpeners over the last few years and have become obsessed with everything to do with knives. I’m always trying to improve my cleaning and sharpening process, and always on the hunt for the next best knife. But when I’m not spending time with my hobby, I’m here, writing about Knives and Sharpeners on KnifePulse to share with you what I learn along the way.

Recent Posts